(a) Field of the Invention
The present invention relates to a deposition apparatus.
(b) Description of the Related Art
A physical vapor deposition (PVD) process, a chemical vapor deposition (CVD) process, and the like have been used as a method of depositing a thin film on a silicon substrate.
However, the existing deposition process has a limitation due to a reduction in the size of a semiconductor device. An atomic layer deposition (ALD) technique has been introduced as a next generation deposition process and the ALD technique has been extensively applicable.
In the ALD technique, a thin film is deposited on a substrate by a self-limiting process, and a process is performed at a temperature range in which a chemical reaction between reaction gases is achieved without being thermally decomposed. Accordingly, the ALD technique is advantageous in that a thin film may be deposited at a lower temperature compared to a temperature required for the existing CVD process.
The ALD technique includes a thermal ALD technique to activate reaction between reaction gases on a substrate by supplying heat energy from a heater supporting the substrate, and a plasma enhanced ALD technique to induce reaction between reaction gases by supplying plasma into a reaction space in addition to a heat source of a heater. Since reaction may be induced if plasma is supplied to reaction gas which may not be reacted in the existing thermal ALD technique, a process that should not be implemented in the thermal ALD technique may deposit a thin film having various thin quality through a plasma ALD technique. In recent years, research and studies with respect to this have been actively performed.
Deposition devices used with plasma use a method of remotely supplying plasma. Since the plasma is remotely supplied, uniform plasma is not supplied on a substrate on which a thin film is deposited and plasma generation efficiency is degraded.
Accordingly, compared with the method of remotely supplying the plasma, as a method capable of increasing efficiency of the plasma, an in-situ plasma deposition apparatus in which plasma is directly generated in a reaction space has been developed since a plasma electrode transferring the plasma defines a reaction space in a reactor.
However, in a case of the in-situ plasma deposition apparatus, with accelerated electrons or ions generated by the plasma, a surface of a thin film formed on the substrate is damaged so that a characteristic of the device is deteriorated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.